Metro Science: Power plants of the future, science says Santa is real, and Trump psychology

A huge source of renewable energy could be covering 71 per cent of the planet's surface — but what are the risks if we figure out how to tap into it?

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Lucas Oleniuk / Toronto Star Staff

This looks like Lake Ontario, but really, it's a huge source of untapped power.

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Every day, all day, water evaporates from the world's oceans, lakes, rivers, puddles and swamps. That motion is equivalent to something like 40 quadrillion watts of energy per year — clean, renewable energy we're leaving on the table. Nowhere near all of it can be harnessed. But according to a paper in Nature Communications, with the right technology, some of it could, and the amount could rival wind and solar. Here's how it could work.

The energy hiding in plain sight

When a liquid is exposed to heat and movement, its molecules speed up and spread out, causing some to escape into the air. That's evaporation. The molecules that escape have more energy (and therefore heat) than the ones left in the liquid. That means there's a flow of energy and heat.

How it could be harnessed

Researchers at Columbia University have made a tiny prototype of an evaporation-powered engine. It includes a slab of sponge-like material with a pair of shutters on top. It hovers just above a body of water. The sponge expands as it absorbs liquid, until eventually the shutters pop open. That motion could be used to power a generator. The sponge contracts as it dries out, the shutters close, and the process starts again.

But wait ...

If it was scaled up and adopted widely, the technology could affect humidity, rainfall and local climate. This would have to be weighed against its advantages. One day, you can imagine giant floating power stations bobbing on the ocean or the Great Lakes — but not significantly disturbing the ecosystem beneath.

istock

Scientists conducting tests on Santa's bones could find themselves on the naughty list

SCIENCE STORIES: The very, very old Saint Nick

A new Oxford University study of bone relics that, according to a 1,000-year-old tradition, belong to Nicholas of Myra (a.k.a. St. Nicholas, a.k.a. Santa Claus), has found they date to the fourth century, when the Christian icon likely died. Thanks to advances in radiocarbon dating technology, scientists were able to use a tiny fragment of bone instead of smashing what's left of Santa to bits, which would have certainly earned them a lump of coal.

Win McNamee

A person's social media posts may hold enough information for psychiatrists to draw conclusions about their mental health, a new analysis says

THE GOLDWATER STANDARD

A new analysis says science does not support the American Psychological Association's Goldwater Rule, which bans members from commenting on the mental health of public figures without examining them. With today's technology, it's possible to gather enough information from friends, family, media reports and the person's own social media posts to provide enough information to diagnose them.

SOUND SMART: Your science vocabulary word for the week

USE IT IN A SENTENCE: All the steam coming off Deborah's body is heating up this dance floor like a convection oven.

DEFINITION: Convection is the heat transfer that happens when hot liquid or gas rises, cools and sinks again, creating a circular current.